It has been common practice to open the full selected length of an artery which is to be cleaned of plaque build-ups and tediously separate the inner layers (i.e. the "core") from the outer layers to remove the plaque build-ups along the length of the artery after which the full length of the opening is sutured closed using the outer layers for the closure. Because such incisions, for example, can extend along the entire length of the leg from the groin to the foot, such a procedure is a massive surgical invasion. As the length of the incision increases, the difficulty of the surgical procedure increases.
Another procedure, involving relatively small incisions at the ends of the artery section to be cleaned, also has been performed in the past for the removal of plaque build-ups. In this procedure, plaque build-ups are removed or loosened by forceps which are introduced at the two incisions to "core out" the artery. To remove residue plaque, a "stripper" (e.g. a catheter-type unit) is passed through the entire blocked artery from the upper incision to the lower incision and a certain, limited amount of residue plaque is pushed out through the lower incision. A swab is secured to the leading end of the catheter-type unit after it has emerged through the lower incision. Upon retraction of the catheter-type unit, the swab carries residue plaque toward and out from the upper incision. Thereafter, the two incisions are closed. Because this procedure is "blind" in that the artery section being cleaned is not open and exposed, it is inherently dangerous. Also, the second incision is necessary either for an exit of plaque or to gain access to the catheter-type unit for affixing the swab.
In another technique for the removal of plaque build-ups, known as gas endarterectomy, a jet of carbon dioxide gas is injected into the wall of an artery to create a "separation plane." A small opening is made in the artery and a special gas spatula, carefully designed not to injure the artery, is passed down the separation plane as carbon dioxide gas passes through the spatula further freeing up the entire length of the inner core. The inner core then is removed by transecting the distal end and pulling the entire core out of the proximal opening in the artery after which the two openings are closed. Because this procedure also is "blind" in that the artery section being cleaned is not open and exposed, it is inherently dangerous. Also, this procedure requires at least two surgical incisions to expose both ends of the artery section to be cleaned and two openings in the artery itself.
Gas endarterectomy also has been carried out by first surgically opening the body part, but not the artery which is to be cleaned, along the full selected length of the artery and then performing the gas endarterectomy by viewing the probing of the artery through the sufficiently transparent artery wall. Such a procedure also is a massive surgical invasion. As the length of the incision increases, the difficulty of the surgical procedure increases.
Because of the difficulties and hazards associated with the surgical procedures described above, bypass surgical procedures became popular. Instead of cleaning out a plaque build-up in an artery, the section of the artery having the plaque build-up is bypassed surgically. Such a bypass procedure also is a massive surgical invasion. As the length of the bypass increases, the difficulty of the surgical procedure increases.
At the present time, there is a trend for reducing the degree of invasion in surgical procedures. Consequently, more and more renewed interest is being expressed in gas endarterectomy which reduces surgical invasion and the period of time the patient must remain in the hospital.